Browse Prior Art Database

Damping Racks

IP.com Disclosure Number: IPCOM000110549D
Original Publication Date: 1992-Dec-01
Included in the Prior Art Database: 2005-Mar-25
Document File: 5 page(s) / 154K

Publishing Venue

IBM

Related People

Ikeda, T: AUTHOR [+4]

Abstract

This invention allows optical cartridges to be slowly ejected from the drive while maintaining relatively high ejection forces. Current optical cartridges have significant forces acting upon them during ejection (including the cartridge shutter door and the drive's shutter arm springs), and if these forces are left undamped, the cartridge can eject onto the floor. This invention uses a damping scheme which allows the cartridge to slowly eject out of the drive.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Damping Racks

       This invention allows optical cartridges to be slowly
ejected from the drive while maintaining relatively high ejection
forces.  Current optical cartridges have significant forces acting
upon them during ejection (including the cartridge shutter door and
the drive's shutter arm springs), and if these forces are left
undamped, the cartridge can eject onto the floor.  This invention
uses a damping scheme which allows the cartridge to slowly eject out
of the drive.

      This invention is unique because it allows a damping action to
be position dependent, not just velocity dependent, as most past
damping techniques.  This is accomplished by using pivoting gear
racks meshed with a black box damping mechanism, as shown in Fig. 1.
Fig. 1 shows the invention configured with two independent racks and
shutter arms.  However, each rack/shutter arm combination is
independent from the other.  Each rack translates (in the X and Y
plane) through its black box damper mechanism as the shutter arm
moves back and forth.  To allow smooth continuous motion, the rack is
free to rotate about its attachment point to the shutter arm.  In
addition, a guide pin is used to keep the rack and damper gear in
mesh.  Fig. 1 shows the shutter arms and racks in a closed position
such that the restoring springs are taut and trying to pull the
shutter arms to the open position.  Fig. 3 shows an arm/rack
combination in both the open and closed positions.

      Another advantage of this invention is its adaptability and
versatility.  A black box damper, which is normally quite bulky, can
be moved away from the mechanism which needs damping, to an area
where more space is available for mounting.  The rack can then be
lengthened or shortened in order to transfer the damping effect from
the black box damper to the applicable mechanism.

      The black box dampener can be considered a generic device, but
the invention assumes a velocity-dependent damping/braking device.
This invention is implemented by 1) allowing the rack to rotate about
the black-box input gear and 2) having the damper apply its
restrictive force about a pivot such that the moment arm is a
function of rack position.  Each of the above points, 1) and 2), are
described in the following two paragraphs.
      1.  Rotating rack effect.  As shown in Fig. 3, location E
(where the rack is attached to the shutter arm) rotates about the arm
pivot, due to the motion of the shutter arm moving, the rack's motion
changes from a predominantly rotating motion to a predominantly
translating motion.  This can be seen more easily in Figs. 2a and 2b.
When the shutter arm is in the open position (Fig. 2a), the rack can
be seen to rotate about the damper.  Three rack positions are shown
in Fig. 2a, including two additional i...